Dynamo-electric machine



(No Model.) 2 Sheets-Sheet 1.

G. W. FULLER.

DYNAMO ELHCTRIC'MAGHINE. I No. 286,414. Patented Oct. 9, 1883.

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2 SheetsSheet. 2.

-(No Model.)

v G. W. FULLER.

DYNAMO ELECTRIC MACHINE. No. 286,414. Patented Oct. 9, 1883.

$516544 7wcma N rEYtRs. mmm c.

UNITED STATES PATENT OEFIcE.

GEORGE IV. FULLER, OF NORWICH, CONNECTICUT.

DYNAMO-ELECTRIC MACHINE.

SPECIFICATION forming part of Letters Patent No. 286,414, dated October9, 1883.

Application filed August 16, 1883. (No model.)

To ctZZ whom it may concern.-

Be it known that I, GEORGE XV. FULLER, of Norwich, Connecticut, haveinvented certain Improvements in Dynamo-Electric Machines, of which thefollowing is a specification.

It is an important obj ect of my invention to simplify the constructionof that class of dynamoelcctri 0 machines in which the inductioncoilstraverse longitudinally the interior and exterior surfaces of a hollowcylindrical core; and I accomplish this result by constructing such acore of one or more spirals, which can be inserted by a corkscrew motioninto induction coils which have been previously wound in the form ofoblong links. WVhen the core is composed of a single spiral, I employ acomparatively thin ribbon, the sides of which are spirally imposed. Ininserting such a spiral into such coils, the adjoining convolutions arecapable of being sprung apart sufiiciently to allow the ends of thecoils to pass between the convolutions. Then two or more spirals areemployed, their convolutions are respectively interplaced. For example,when two spirals are employed, the pitch of each spiral is regulatedwith reference to preserving sufficient space between these convolutions to admitthe convolutions of a similar spiral and such space maybe of sufficient width to allow the passage through it of the ends ofthe coils in the act of inserting the spirals into the coils. Bysupporting the spiral or spirals of which my core is composed upon or bymeans of devices composed of nonconducting materials, so that there isno outside electrical connection of the terminals of a spiral with eachother, I am enabled to avoid the presence in the core of a completecircle of metal, or closed electrical circuit, in which currents ofelectricity can be established by induction. At the same time, by usingiron, either wrought or cast, as the material for the spirals, I amenabled to have a practically closed magnetic circuit.

My invention is applicable to dynamoelectric machines of various types,as well to those having annular armature cores as to those havingarmatures the cores of which are cylindrical or spherical in form. Themechanical advantages possessed by my spiral core are of considerableeconomicimportance,

especially in the case of an annular or hollow cylindrical core, whichis to be longitudinally traversed interiorly and exteriorly byinduction-coils. Ordinarily such coils are applied by winding the wireof which. they are composed upon the core itself, which is a labor ous,tedious, and expensive operation. By my invention the coils may be woundupon a lathe into suitably-formed links, which is a much easier and moreeconomical method of winding them. The spi "als composing the core maybe successively inserted through these links by a corkscrew motion.

The accompanying drawings, illustrating my invention applied to a hollowcylindrical armature, are as follows:

Figure 1 is an end elevation of the armature, showing the coils in placeand one of the star-shaped heads by means of which the core is supportedupon the armature-shaft. Fig. 2 is a longitudinal section through theline 00 m on Fig. 1. Fig. 8 is a side elevation of the two spirals,showing one spiral fully inserted through one of the induction-coils andthe other partially inserted. Fig. at is an isometrical perspective ofone of the segments, which are curved upon the same radius as the spiraland are interposed between the ends of the core, respectively, and theends of the induction-coils, and are fastened to the arms of thestar-shaped heads by which the core is supported.

The drawings represent an armature of the class in which theconvolutions of each of the induction-coils, respectively, traverse in alongitudinal direction both the interior and the exterior surfaces ofthe hollow cylinder which constitutes the armaturecore. Theinductioncoils are symmetrically arranged upon the holb and I).

1O cylindrical core, and which are provided with facings of insulatingmaterial, upon which the concave surfaces of the spirals O G bear.

The two spirals O C have the same axis and the same pitch. Theirconvolutions, which, as

1 5 will be seen, are inter-placed are prevented from contact with eachother by means of the tablets of insulating material a, which areinserted in those parts of the spaces between the convolutions which arein radial alignment with the clamping-bolts b.

The two spirals O and 0, when their convolutions are interplaced, form ahollow cylinder, which is centralized by the bearing of its interiorsurface upon the facings of insulating 2 material laid upon theprojecting fingers B This cylinder is stayed in position longitudinallyby two rings, D and D, each composed of short segments d, curved uponthe same radius as the spirals, and of such thickness that they can beinterposed between the end of the cylinder and the ends of theinduction-coils. The segments d are fastened to the ends of the radialarms B by the screw d0, Strips of insulating material are interposedbetween the p 3 5 ends of the cylindrical core and the rings D D,respectively.

The induction-coils E are wound on a lathe in the form offiattened'links with straight parallel sides, and the spirals aresucces- 0 sively inserted through these links by a corkscrew motion. Thepitch of the spirals is such that the space between any two of theconvolutions is large enough to allow the passage of the end 6 of acoil. One of the spirals, O, is

5 first fully inserted through all the coils, and

there is then room for the similar insertion of the second spiral, O.The segments d, composing the rings D and D, are then inserted betweenthe ends of the coils and the ends of the core, and the coils aresymmetrically grouped around the perimiter of the hollow cylinder,leaving at each end six spaces for the arms 13 and fingers B of theheads, respectively. The tablets of insulating material 5 having beenplaced between the convolutions,

the bolts 5 are inserted, and the heads 13 and the spirals are thenclamped together by the application of the nuts 1/ and V.

The symmetrical arrangement of the circle of induction-coils E iseffected by the spacingblocks E, which are deposited in the spacesbetween the exterior portions of the coils, and are held in position bythe clamping-bands E E or by wrappings of fine wire, which surround thearmature, as shown in the draw- 1ngs.

. The hubs B of the heads B are fixed upon the shaft A by means of thekeys A, or otherwise, so that when the shaft revolves it carries with itthe spirals, which constitute the core of the armature upon which thearmature-coils are supported. The armature is then appropriatelyarranged in a dynamo-electric machine, and the coils are suitablyconnected in any desired manner.

In forming the spirals which constitute the core I preferably prepare ahollow cylinder of soft iron, and then mount it in a lathe, and, havingturned it to the required diameter,

then cut it into two spirals of like pitch by the use of adouble-pointed chaser having the required lead. It will, however, ofcourse be understood that such spirals can be made by bending rods orwires of soft iron into the required form, as is more fully described inanother pending application.

I claim as my invention 1. In a dynamo-electric machine, a hollowcylindrical armature the core of which is composed of one or morespirals, in combination with induction-coils the convolutions of each ofwhich traverse longitudinally the interior and exterior surfaces of thecylinders composed of the said spiral or spirals, and means forsupporting the said cylinder andinduction-coils upon the armature-shaft.

2. A hollow cylindrical armature-core composed of iron spirals of likediameter and pitch, suitably supported upon a rotating shaft, butinsulated therefrom, and having their convolutions, respectively,insulated from each other, for the purpose of preventing the presence inthe core of a continuous metallic circuit, in which currents ofelectricity can be established by induction when the said core isprovided with induction-coils and employed as an armature in adynamo-electric machine.

3. A hollow cylindrical armature-core composed of one or more spirals,in combination with the star-shaped heads B, aflixed to thearmature-shaft A and provided with the laterally-projecting fingers B,for the purpose of centralizing the said core relatively to thearmature-shaft.

4. A hollow cylindrical armature-core composed of one or more spirals,substantially as set forth, and the rings D and D, each composed of thesegments d, secured to the radial arms B of the heads B, and means forlongitudinally clamping the heads and core together, substantially asand for the purpose set forth.

GEO. W. FULLER.

Witnesses:

JOHN E. EARLE, Jos. O: EARLE.

